Q: Setting up find my iphone with  different iCloud accounts

You want the free Find My Friends App.  It's available in the app store.  It allows you to track whomever you want (that allows it).

I'll post a link

https://itunes.apple.com/us/app/find-my-friends/id466122094?mt=8

Essentially, you request on 1 device, accept on the other.  You can use parental controls to keep them from disabling.

iOS Restrictions:

http://support.apple.com/kb/HT4213

iTunes: Parental Controls:

http://support.apple.com/kb/HT1904

Mac App Store Parental Controls:

http://support.apple.com/kb/PH11496

Mac OS X: Parental Controls (video)

http://support.apple.com/kb/VI28

Find my Phones is a similar function , but separate.  It should remain on (and requires a password to turn off).  You could technically use FMI on 1 device to locate the others, but you would have to type in the apple ID and passwords for each separate device.  That's why I think FMF is the better choice for you to keep track of your family (my wife calls it stalking).

Yes.  You should keep the FMI on each device - if one is ever lost, you can use the FMI app on another device to Play a sound, lock the device, put it in lost mode, or remote erase it.  You can do the same things using an internet browser at www.icloud.com .  But FMI is handier.

I hope this helps.

LOL.   Yes it is. 

Good luck to you, and welcome to the forums.